In a heavy large saucepan over medium-high heat, warm the oil. Add the onion, chiles, ginger and cumin seeds. Saute until the onion is tender, about 6 minutes. Add the chickpeas with their liquid, tomatoes with their juice, lime juice, 1/2 teaspoon of the garam masala and turmeric. Bring to a boil, and then reduce the heat and simmer for 5 minutes to blend the flavors.

Add the cauliflower, potatoes and 1 cup (8 fl. 0z./250 ml.) water, and simmer until the potatoes are tender, stirring occasionally and adding more water if dry, about 15 minutes. Stir in the remaining 1/4 teaspoon garam masala. Season to taste with salt and pepper.

Divide the rice, if using, among 4 warmed shallow bowls. Spoon the curry over the top, sprinkle with cilantro and serve right away. Serves 4.